This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A023303 #22 Sep 08 2022 08:44:47 %S A023303 47,67,97,137,307,1427,2857,6047,6997,9377,12097,16057,24197,32117, %T A023303 35117,36877,44507,46687,54517,55487,64877,71327,71807,76537,89017, %U A023303 92387,94427,100057,132707,142057,153077,160207,184777,186647,194027,200117,205237 %N A023303 Primes that remain prime through 4 iterations of function f(x) = 2x + 3. %C A023303 Primes p such that 2*p+3, 4*p+9, 8*p+21 and 16*p+45 are also primes. - _Vincenzo Librandi_, Aug 04 2010 %H A023303 Harvey P. Dale, <a href="/A023303/b023303.txt">Table of n, a(n) for n = 1..1000</a> %t A023303 Select[Prime[Range[20000]],And@@PrimeQ[NestList[2#+3&,#,4]]&] (* _Harvey P. Dale_, Aug 12 2012 *) %o A023303 (Magma) [ p: p in PrimesUpTo(300000) | IsPrime(p) and IsPrime(2*p+3) and IsPrime(4*p+9) and IsPrime(8*p+21) and IsPrime(16*p+45)] // _Vincenzo Librandi_, Aug 04 2010 %Y A023303 Subsequence of A023204. %K A023303 nonn %O A023303 1,1 %A A023303 _David W. Wilson_